Rotor drive for pulsato apparatus



P 1966 D. .1. LESLIE 3,245,284

ROTOR DRIVE FOR PULSA'I'O APPARATUS v I Filed May 31, 1963 4Sheets-Sheet 1 INVENTOR.

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ROTOR DRIVE FOR PULSATO APPARATUS Filed May 31, 1863 4 Sheets-Sheet 4I40. 10. Z0 99 Pulse/o M 5 V ganoam Slow Speed W as ag P/ Random SlawSpeed c M r. 0 $1 Noise Sou/re Frequency Amp/if/qr INVENTOR. v.DOMQLD zLESLIE United States Patent 3,245,284 ROTOR DRIVE FOR PULSATO APPARATUSDonald J. Leslie, 313 S. Fair Oaks Ave., Pasadena, Calif. Filed May 31,1963, Ser. No. 284,627 19 Claims. (Cl. 74661) This invention relates tomusical instruments, particularlyelectronic organs, and especially toapparatus for producing pulsato by acoustic devices. Such apparatus isshown and described in my Reissue Patent No. 23,323 dated January 9,1951, and entitled Rotatable Tremulant Sound Producer.

During the course of a musical composition, the organist often desiresto change the type of pulsato to be added. He may, for example, desireto select acoustic pulsato, electronic pulsato, or no pulsato. Theseselections are customarily made by operating organ stops or switches. Insome applications, the switches merely alter the course of theelectrical signal from rotary pulsato apparatus to a nonrotary speaker.Alternately, the acoustic pulsato apparatus, including moving parts suchas rotors, may be stopped and started by the operation of switches.

When acoustic pulsato is not desired, it may yet be desirable slowly toshift the sound source at a rate well below pulsato frequencies, as forexample, two-thirds of a cycle per second. By imparting phase shifts bysuch means, a characteristic dullness or flatness is avoided, especiallyif the rate is varied to produce random phase shifts. The phase shiftsso produced simulate, in general, phase shifts commonly produced bymovement of swell shutters in pipe organ systems.

One of the objects of this invention is to provide a simple systemwhereby a rotor may produce, in addition to pulsato, phase shiftsregularly or randomly.

If acoustic pulsato is controlled by starting and stopping a rotor, itis desirable to accomplish the change quickly in order to avoid certaindroning sounds. One of the objects of this invention is to provide asimple, inexpensive motor drive for a pulsato rotor that is capable ofbraking the rotor as well as producing slow rotation.

Still another object of this invention is to provide a motor drive forperforming these various functions that utilizes two quite inexpensivemotors, one motor having a shaft at one end connected to the pulsatorotor, and the other end connected to the other motor only upondeenergization of the one motor and energization of the other.

Still another object of this invention is to provide a compact motorstructure of this character that can be installed and replaced as aunit.

Still another object of this invention is to provide novel circuitry forcontrolling the two motors to achieve pulsato, slow rotation of uniformor of varying rates, or automatic braking.

This invention possesses many other advantages, and has other objectswhich may be made more clearly apparent from a consideration of severalembodiments of the invention. For this purpose, there are shown a fewforms in the drawings accompanying and forming part of the presentspecification. These forms will now be described in detail, illustratingthe general principles of the invention; but it is to be understood thatthis detailed description is not to be taken in a limiting sense, sincethe scope of the invention is best defined by the appended claims.

Referring to the drawings:

FIGURE 1 is a front elevational view of a pulsato unit incorporating thepresent invention;

FIG. 2 is a bottom plan view thereof;

3,245,284 Patented Apr. 12, 1966 FIG. 3 is a fragmentary enlargedsectional view taken along a plane corresponding to line 33 of FIG. 2;

FIG. 4 is a sectional view similar to FIG. 3 but illustrating the partsin an alternate position;

FIG. 5 is a sectional view taken along a plane corresponding to line 5-5of FIG. 3;

FIG. 6 is a wiring diagram showing an elementary control circuit forselective operation of the motors;

FIG. 7 is a wiring diagram showing a circuit for use with the motors,whereby various modes of operation thereof may be selected; namely,pulsato, stop, off, slow, and cycle slow;

FIG. 8 is a wiring diagram illustrating a circuit for use with themotors, whereby some of the modes of operation of the form illustratedin FIG. 7 may be achieved but with different circuit elements; and

FIGS. 9, 10 and 11 each diagrammatically illustrate different controlcircuits for producing random operation of the slow speed motor.

In FIG. 1 there is illustrated a pulsato unit 10 that is adapted to beinstalled within the enclosure of an organ console. The pulsato unit 10includes a number of ele ments 11, 12, 13 and 14 forming a four-sidedframe. The frame elements 12 and 14 are generally square, and spacedapart in parallel relationship by the other frame elements 11 and 13.The frame element 14 forms the base for suspension of a pulsato drum 15as by the aid of the U-shaped bearing bracket 16. A non-rotary speakerstructure (not shown) is accommodated between the base plate 14 and theparallel frame member 12. The frame member 11 has an extended end thatcarries an attaching backet 17 whereby the entire unit may be secured ata corner or at some other suitable position in the console cabinet.

The pulsato rotor 15 is driven by the aid of a pulley structure thatincludes pulley elements 18 and 19 of the rotor 15 and the motor 20respectively, together with a belt 21. The pulley ratio is about one tofour or one to five whereby, with a four pole motor 20, the rotor isoperated at about 400 r.p.m. or almost 7 c.p.s. Which is a suitablepulsato rate.

The motor structure 20 is supported on the base frame member 14 by theaid of a stamped centrally offset mounting bracket 22. The mountingbracket 22 may be attached to the base member 14 by the aid of screws 23and 24 and Wing nuts 25 and 26. Suitable resilient pads are interposedbetween the mounting bracket 22 and the base member 14 for dampingpurposes.

The motor 20 may be an inexpensive shaded pole motor available as astandard article of commerce. The motor 20 has end caps or brackets 27and 28 on opposite sides of the stack of stator laminations 29. Each endcap has a series of interiorly threaded embossments as at 30 (FIG. 3)whereby suitable attachment may be made at opposite ends of the motor.The threaded embossments 30 at the upper bearing bracket 27 (FIG. 1)serve as a means for cantilever attachment of the motor 20 to themounting bracket 22. For this purpose suitable screws 31 are provided.Acoustic damping pads 32 are also used with the screws 31.

The motor shaft 33 projects through the mounting bracket 22, and thepulley element 19 is mounted upon this end of the shaft.

When pulsato is not desired, it may be nevertheless desirable to operatethe rotor 15 at a slow speed, say of the order of ten revolutions perminute, in order to produce a certain source indefiniteness. For thispurpose the shaft 33 of motor 20 is operated at its other end bysecondary motor structure 34. The motor structure 34 may be a 2-pole,high-speed small inexpensive shaded pull motor such as may be availableas a standard article 3 of commerce. The motor 34 has an extended shaft35 capable of engaging a pulley wheel 36 attached to the depending endof the shaft 33.

The motor 34 has a pair of die cast bearing brackets 37 and 38 by theaid of which the motor is supported. The bearing bracket 37 is generallyof H-shaped configuration as shown in FIG. 5 with arms 39 and 40abutting one side of the stack of stator laminations 41. These arms 39and 40 have aperture recesses (not shown) in alignment with holesthrough the stack of laminations 41. The lower bearing bracket 38 alsohas arms 42 and 43 provided with through apertures. Screws 44 and 45pass through the bearing bracket arms 42 and 43 through the stack oflaminations 41 to engage the apertured recesses of the arms 39 and 40 onthe opposite sides of the stack. A rotor assembly 46, which includes theshaft 35, is supported by self-aligning bearings 47 and 48 carried bythe brackets 37 and 38.

The upper bearing bracket 37 also serves as a means whereby the motor 34is suspended. For this purpose the upper ends of the arms 39 and 40 areattached to a plate 49 by the aid of studs 50 and 51 projecting from thebracket arms 39 and 40. Nuts 52, together with damping pads 53 cooperatewith the studs to attach the motor 34. A U-shaped bracket 54 in turnattaches the plate 49 to the main drive motor 26.

The central portion of the bracket 54 abuts the three threaded bosses 30of the motor cap 28, and is fastened thereto by screws 55. The bracket54 and plate 49 form space 56 in which the pulley wheel 36 isaccommodated. The plate 49 has an opening 57 through which the shaft 35projects so as to be engageable with the rim of the pulley wheel 36. Afriction ring 58 is carried on the rim of the wheel 36, and which isengaged by the shaft 35. Preferably the ring 58 has a circular crosssection so as to facilitate movement of the shaft into engagement withthe wheel 36 in a manner presently to be described.

The shaft 35 is capable of axial movement between positionscorresponding to engagement with the friction wheel 58 and clearancewith respect thereto, and as depicted respectively in FIG. 3 and FIG. 4.A compression spring 59 surrounding the shaft 35 and interposed betweenone end ring 60 of the rotor and the bearing 47 normally urges the shaft35 and the rotor assembly 46 to the lower limited position of FIG. 4.This limited position is determined by a stop washer 61 located justbeyond the stack of rotor laminations. An O-ring 62 is interposedbetween the stop washer 61 and the other end ring 63 of the rotor,thereby forming a suitable cushion.

In the disengaged position illustrated in FIG. 4, the rotor laminations60 are out of alignment with the stator laminations 41. Uponenergization of the motor 34, and due to the reluctance effect, therotor assembly will be pulled into the aligned position shown in FIG. 3,and against the force of the compression spring 59. Thus, as the motoris energized, the rotor moves from a position of larger reluctance (FIG.4) to a position of smaller reluctance (FIG. 3). In the position of FIG.3, the shaft 35 easily rides over the O-ring 58, compressing itslightly, thus establishing engagement with the pulley wheel 36. Thearea of contact is yet sufficiently small to permit the spring 59 toretract the rotor assembly 46 when the motor 34 is de-energized.

By the use of two standard inexpensive motors 20 and 34, alternate modesof operation of the pulsato rotor 15 are possible. A wiring diagram isdepicted in FIG. 6. A main switch 70, upon closure, connects a switcharm 71 of a double throw selector switch to one source terminal 72. Theother source terminal 73 is directly connected to one terminal 74 of themotor 20 as well as to one terminal 75 of the motor 34. The otherterminals 76 and 77 of the motors 20 and 34 respectively connect toopposite contacts 78 and 79 cooperable with the switch arm 71.-

When the switch arm 71 is in the full line position illustrated, themotor terminal 76 is connected via contact 78 and the switch arm 71 tothe source terminal 72, and the motor 20 is operated. The other terminal77 of the motor 34 is open circuited and accordingly the spring 59positions the rotor assembly to the inactive position of FIG. 4.However, upon movement of the switch arm 71 to the dotted line position,the motor 20 is de-energized and the motor 34 is operative. Accordingly,the shaft 35 is moved upwardly by the reluctance effect and slowrotation is imparted to the shaft 33 at a ratio corresponding to thediameters of the shaft 34 and the pulley wheel 36. Using a two polemotor, the ratio is approximately one to twenty to produce a rotation ofabout 10 rpm.

Depending upon the orientation of the pulsato unit 10 in the cabinet,the weight of the rotor assembly 46 may assist or oppose the compressionspring 59. Accordingly, depending upon the particular installation, anappropriate spring 59 is chosen.

Depending upon the desired slow speed of the rotor 15, the pulley 36 canbe changed after first unloosening the set screw 79. An adapter sleevecan then be telescoped over and fastened to the projecting end of theshaft 35, or alternately the position of the rotor on the mounting plate49 can be changed.

In order to stabilize the motor 34, a stud 81 is attached to the stackof stator laminations 41 at a place adjacent the relatively heavy coilstructure 82. The stud 81 passes upwardly through the plate 49 and issuitably attached thereto.

By quickly moving the switch 71 from the full-line position to thedotted-line position of FIG. 6, the rotary apparatus is braked by theaction of the motor 34 in its slow speed mode. The rotary apparatus isquickly braked to the speed of the motor 34-.

In the arrangement illustrated in FIG. 7, the motors 20 and 34 areprovided as before. A selector switch 83 is provided that has fivepositions: pulsato, stop, off, slow, and cycle slow. The selector switch83, may, by way of example, be of the rotary type having three separatearms 84, 85 and 86, all operated in unison as indicated by the dottedline 87.

In the first position corresponding to pulsato, a circuit is establishedto the main motor 20 via contact arm 84 and a contact 88. Thus, one sideof the arm 83 connects to one line 89 of the source, and the contact 88connects to one side of the motor 20. The other side of the motorconnects to another line 90 of the source. The pulsato motor 20 isoperated only when the switch 83 is in this first position.

When the switch 83 is moved to the second or stop position, a circuit isestablished for the slow motor 34 in series with normally closed thermalcontacts 135. Thus, the arm 84 now engages a contact 91 that connects toone side of the motor 34 via the thermal contacts 135. The other side ofthe motor 34 connects to the line 90.

A heater 92 is also energized when the selector switch 83 is moved tothe second or stop position. Thus, the arm 85 is connected to the line89, and a contact 93 engaged by the arm at the second position isconnected to one side of the heater 92. The other side of the heaterconnects to the other line 90.

When the selector switch 83 is first moved to the off position, acircuit for the slow motor 34 is established, and the rotary apparatusis braked. After a period of time the heater 92 causes the thermalcontacts to open and the apparatus coasts to a final stop.

At the third position all of the circuits are open, corresponding to oAt the fourth position of the selector switch 83, the heater 92 is outof circuit but a circuit is established to the slow motor via thethermal contacts 135 which in this case remain closed. Accordingly, themotor 34- continues to operate the rotary apparatus at slow speed.

At the fifth position of the selector switch 83, the heater 92 is nowplaced in parallel to the slow motor 34 and thus in serial dependencyupon the thermal contacts 135. For this purpose, the switch arm 86 isconnected to one side of the heater 92, and the contact 93 engaged bythe arm 86 is connected to the corresponding side of the motor 34, theother side of the heater 92 remaining connected to the line 90. Thus,when the selector switch 83 is at the fifth position, the heater 92 willderive energization for a period of time until the thermal contacts 135open. The circuit for the heater 92 is then interrupted and accordinglythe contacts 135 are permited to cool and close. Upon reclosure, boththe motor 34 and the heater 92 are energized. Depending upon the rate ofheat how, the slow motor 34 is operated for certain periods of time,producing a desirable effect.

In moving the selector switch 83 which a pulsato position to off, atleast momentary engagement is made with the contact 91. This results insome braking of the pulsato rotor depending upon the speed that theswitch 83 is moved. If the switch is moved deliberately and slowly,substantial braking will be produced.

In the form of the invention illustrated in FIG. 8, a selector switch 95has four positions, corresponding to pulsato, stop, off and slow. In thestop position, the slow motor 34 is energized through a thermistor 96 sodesigned that it is capable of attaining a resistance value adequate topreclude rotation of the slow motor 34. Thus, as the stop contact isfirst engaged, the motor has minimum resistance and the rotationalenergy of the apparatus is dissipated. Ultimately and due to the actionof the increasing resistance of the thermistor 96, the motor 34 stops.

In the off position, of course no circuits are effective.

In the slow position of the selector switch 95, a circuit is establishedto the motor 34 independently of the thermistor 96.

In the form of the invention illustrated in FIG. 9, a selector switch 97is illustrated that has four positions: pulsato, slow, off, and randomcycle. The pulsato, off, and slow positions are the same as in the formof FIG. 8. At the random cycle position, the slow motor 34 is placed incircuit with a switch 98 that operates randomly to open and close by anysuitable means. For example, the switch 98 may be operated by anirregular cam driven by a motor. The motion of the drum is thusirregular and a desirable effect is achieved.

In the form of the invention illustrated in FIG. 10, a selector switch99 has three positions corresponding to pulsato, random slow speed, andoff. In the random slow speed position, an energization circuit isestablished to the slow motor 34 in serial dependency with a variableimpedance element in the form of a photoresistive cell 100. A lightsource 101 affects the cell 100 in varying degrees depending upon theposition of a disc 102. The disc 102 has filters of various densitiesand arcuate widths for shielding more or less of the light from thesource 101 from the cell 100. The disc 102 is driven by a motor 103, theenergization circuit of which is also established when the selectorswitch 99 is at the random slow speed position. The light source 101 maybe electrical, and, as illustrated, its energization circuit parallelsthe motor 103. As the disc 102 rotates, more or less resistance is incircuit with the motor and the motor 34 operates at varying speedsrather than in interrupted fashion.

The form illustrated in FIG. 11 is similar to that illustrated in FIG.10, except that the light source 104 in this instance is made variable,thereby avoiding the necessity of a variable density or variableconfiguration disc. For this purpose, the light source 104 is operatedby an amplifier 105 driven by a suitable noise source 106. The amplifier105 and noise source 106 are energized when the selector switch 107 ismoved to the random slow speed position. The amplifier 105 emphasizeslow frequency noises so that the change in resistance of thephotoresistive cell 108 takes place at an adequately slow rate to permitthe motor 34 to follow the same.

The inventor claims:

1. In apparatus for producing pulsato by the aid of a rotary device: amain drive motor for operating said rotary device, and having a shaft;means coupling one end of said shaft to said rotary device; saidcoupling means and said main drive motor being designed to operate saidrotary device at a rate to impart pulsato; a secondary drive motorhavinga stator and an axially movable rotor assembly; said rotorassembly being movable between alternate positions of larger and smallerreluctance with respect to said stator, and movable to the position ofsmaller reluctance upon energization of said secondary drive motor;means causing the rotor assembly to move to the position of largerreluctance upon deenergization of said secondary motor; and axiallyseparable coupling means between the rotor assembly and the other end ofsaid shaft and operable upon movement of said rotor assembly to saidposition of smaller reluctance; said axially separable coupling meansand said secondary drive motor being designed to operate said rotarydevice at a small fraction of its pulsato speed for producingindefiniteness in source location.

2. The combination as set forth in claim 1 in which said axiallyseparable coupling includes a pulley wheel mounted on said other shaftend and a shaft forming a part of said rotor assembly movable to engageand disengage said pulley wheel.

3. The combination as set forth in claim 2 together with a friction ringinterposed between said rotor assembly shaft and said pulley wheel, andshaped so as to form a wedge therebetween.

4. The combination as set forth in claim 2 together with a friction ringhaving a generally circular crosssection and mounted on the rim of saidpulley wheel for wedging between the rotor assembly shaft and the saidpulley wheel rim to establish a friction driving connection.

5. In apparatus for producing pulsato by the aid of a rotary device: asupport for the rotary device; a main drive motor for operating saidrotary device, and having a pair of end brackets and a shaft accessiblebeyond the end brackets; means mounting one of the end brackets to thesupport; means coupling said rotary device to the shaft end adjacentsaid one end bracket; said coupling means and said main drive motorbeing designed to operate said rotary device at a rate to impartpulsato; a secondary drive motor attached to and suspended by the otherend bracket of said main drive motor, and having a stator and an axiallymovable rotor assembly; said rotor assembly being movable betweenalternate positions of larger and smaller reluctance with respect tosaid stator, and movable to the position of smaller reluctance uponenergization of said secondary drive motor; means causing the rotorassembly to move to the position of larger reluctance upondeenergization of said secondary motor; and axially separable couplingmeans between the rotor assembly and the other end of said shaft andoperable upon movement of said rotor assembly to said position ofsmaller reluctance; said axially separable coupling means and saidsecondary drive motor being designed to operate said rotary device at asmall fraction of its pulsato speed for producing indefiniteness insource location.

6. The combination as set forth in claim 5 in which said axiallyseparable coupling includes a pulley wheel mounted on said other shaftend and a shaft forming a part of said rotor assembly movable to engageand disengage said pulley wheel.

7. The combination as set forth in claim 6 together with a friction ringinterposed between said rotor assembly shaft and said pulley wheel, andshaped so as to form a wedge therebetween.

8. The combination as set forth in claim 6 together with a frictionringhaving a generally circular crosssection and mounted on the rim of saidpulley wheel for wedging between the rotor assembly shaft and the saidpulley wheel rim to establish a friction driving connection.

9. In apparatus for producing pulsato by the aid of a rotary device, thecombination with said rotary pulsato device of: first and second motormeans for operating said rotary device respectively at pulsato rates andat rates corersponding to a small fraction of pulsato rates; aselectively operable energization circuit for said first motor means; aselectively operable energization circuit for the second motor means;and selectively operable time delay means for interrupting theenergization circuit for said second motor means.

10. In apparatus for producing pulsato by the aid of a rotary device,the combination with said rotary pulsato device of: first and secondmotor means for operating said rotary device respectively at pulsatorates and at rates corresponding to a small fraction of pulsato rates; aselectively operable energization circuit for said first motor means; aselectively operable energization circuit for the second motor means andfunctioning in accordance with the passage of time for producingnonuniform operation of said second motor means.

11. In apparatus for producing pulsato by the aid of a rotary device,the combination with said rotary pulsato device of: first and secondmotor means for operating said rotary device respectively at pulsatorates and at rates corresponding to a small fraction of pulsato rates; aselectively operable energization circuit for said first motor means; aselectively operable energization circuit for the second motor means;and selectively operable means functioning in accordance with thepassage of time for cyclically interrupting the energization circuit ofsaid second motor means.

12. In apparatus for producing pulsato by the aid of a rotary device,the combination with said rotary pulsato device of: first and secondmotor means for operating said rotary device respectively at pulsatorates and at rates corresponding to a small fraction of pulsato rates; aselectively operably energization circuit for said first motor means; aselectively operable energization circuit for the second motor means;selectively operable time delay means for interrupting the energizationcircuit for said second motor means; and selectively operable means forcyclically interrupting the energization circuit of said second motormeans.

13. In apparatus for producing pulsato by the aid of a rotary device,the combination with said rotary pulsato device of: first and secondmotor means for operating said rotary device respectively at pulsatorates and at rates corresponding to a small fraction of pulsato rates; aselectively operable energization circuit for said first motor means; aselectively operable energization circuit for the second motor means;and selectively operable means functioning in accordance with thepassage of time for interrupting the energization circuit of said secondmotor means at random intervals.

14. In apparatus for producing pulsato by the aid of a rotary device:first and second motor means for operating said rotary devicerespectively at pulsato rates and at rates corresponding to a smallfraction of pulsato rates; a selectively operable energization circuitfor said first motor means; a selectively operable energization circuitfor the second motor means including a variable impedance element; andselectively operable means for randomly varying the impedance of saidelement for producing nonuniform rotation of said second motor means.

15. The combination as set forth in claim 14 in which said impedancevarying means comprises a light source energized at random intensity,and in which said variable impedance element comprises a photosensitiveelement affected by said source.

16. The combination as set forth in claim 14 in which said impedancevarying means comprises a light source in combination with a movableshield therefor having a light transmission characteristic dependentupon position, and in which said variable impedance element comprises aphotosensitive element receiving luminous flux from said source independence upon said shield.

17. In apparatus for producing pulsato by the aid of a rotary device;first and second motor means for operating said rotary devicerespectively at pulsato rates and at rates corresponding to a smallfraction of pulsato rates; a selectively operable energization circuitfor said first motor means; a selectively operable energization circuitfor the second motor means including an impedance element that increasesits resistance as a function of time thereby reducing the energizationof said second motor means.

13. In apparatus for producing pulsato by the aid of a rotary device,the combination with said rotary pulsato device of: first and secondmotor means for operating said rotary device respectively at pulsatorates and at rates corresponding to a small fraction of pulsato rates; aselectively operable energization circuit for said first motor means; aselectively operable energization circuit for the second motor means anda selector switch having successive switching positions corresponding,first, to energization of said first motor means, second, toenergization of said second motor means and, third, to off.

19. In combination: a pulsato device; means mounting the pulsato devicefor rotation about an axis; motive means for imparting rotation to saidrotary device; and selectively operable means for determining high andlow rates of rotation of said rotary pulsato device, the high rate ofrotation producing pulsato, and the low rate of rotation producing phaseshifts.

References Cited by the Examiner UNITED STATES PATENTS DON A. WAITE,Primary Examiner.

1. IN APPARATUS FOR PRODUCING PULSATO BY THE AID OF A ROTARY DEVICE: AMAIN DRIVE MOTOR FOR OPERATING SAID ROTARY DEVICE, AND HAVING A SHAFT;MEANS COUPLING ONE END OF SAID SHAFT TO SAID ROTARY DEVICE; SAIDCOUPLING MEANS AND SAID MAIN DRIVE MOTOR BEING DESIGNED TO OPERATE SAIDROTARY DEVICE AT A RATE TO IMPART PULSATO; A SECONDARY DRIVE MOTORHAVING A STATOR AND AN AXIALLY MOVABLE ROTOR ASSEMBLY; SAID ROTORASSEMBLY BEING MOVABLE BETWEEN ALTERNATE POSITIONS OF LARGER AND SMALLERRELUCTANCE WITH RESPECT TO SAID STATOR, AND MOVABLE TO THE POSITION OFSMALLER RELUCTANCE UPON ENERGIZATION OF SAID SECONDARY DRIVE MOTOR;MEANS CAUSING THE ROTOR ASSEMBLY TO MOVE TO THE POSITION OF LARGERRELUCTANCE UPON DEENERGIZATION OF SAID SECONDARY MOTOR; AND AXIALLYSEPARABLE COUPLING MEANS BETWEEN THE ROTOR ASSEMBLY AND THE OTHER END OFSAID SHAFT AND OPERABLE UPON MOVEMENT OF SAID ROTOR ASSEMBLY TO SAIDPOSITION OF SMALLER RELUCTANCE; SAID AXIALLY SEPARABLE COUPLING MEANSAND SAID SECONDARY DRIVE MOTOR BEING DESIGNED TO OPERATE SAID ROTARYDEVICE AT A SMALL FRACTION OF ITS PULSATO SPEED FOR PRODUCINGINDEFINITENESS IN SOURCE LOCATION.